Dosimetry, efficacy and safety of radiolabelled somatostatin receptor antagonist in patients with metastatic pheochromocytoma or paraganglioma

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Introduction: Metastatic pheochromocytomas and paragangliomas (mPPGLs) are rare neuroendocrine tumours with a heterogenous phenotype and a variable treatment response. The SSTR antagonist [177Lu]Lu177Lu-DOTA-JR11 (177Lu-JR11) offers potentially increased tumour doses than standard radioligand therapy (RLT) with [177Lu]Lu-DOTA-TOC (177Lu-TOC).

Aim(s): Intrapatient comparison of tumour dosimetry of 177Lu-TOC versus 177Lu-JR11 in patients with progressive mPPGLs, non-responsive to conventional treatment. Secondary objective was assessment of efficacy and safety of 177Lu-DOTA-JR11 therapy in these patients.

Materials and methods: In this retrospective study we included 6 patients with aggressive, mPPGLs treated with 1-2 cycles 177Lu-DOTA-TOC (7.2-7.5 GBq/cycle) followed by one cycle 177Lu-DOTA-JR11 (2.8-4.2 GBq/cycle) at an interval of 10-12 months. Endpoints: imaging-based tumour absorbed doses (3D dosimetry using Olinda), safety (CTCAE V5.0 criteria), PFS and symptoms control.

Conference:

Presenting Author: Lider S

Authors: Lider Burciulescu S, Schmidt F, McDougall L, Bernhardt P, Mushaweh A,

Keywords: Metastatic PPGL, radioligand therapy, somatostatin receptor antagonist, dosimetry,